docboot freeze

Dan Brown dan_brown at
Mon Mar 14 16:02:59 EST 2005

Matt Garratt wrote:
> I am still trying to get docboot to work from a DOC200 after giving up on
> grub after much time wasted. Getting the DOC to boot is the most frustrating
> thing I have done for quite a while. I get as far as:
> Loading kernel.......Loading initrd.....

Hi, Matt.  Sorry I didn't respond to your message sooner.  I'm sorry to 
hear about the trouble you're having.  My guess is that the newly-added 
initrd support in DOCBoot is buggy in some fashion -- it's received very 
little testing.

To help me figure this out, can you tell me how much RAM your system has?

Also, please try the following test:  Install DOCBoot WITHOUT the 
ramdisk image (but with the same cmdline).  This, of course, should fail 
when the kernel tries to load data from /dev/ram0.  But at least you 
should see all the initial kernel messages before it tries to mount the 
root filesystem.  The fact that you currently don't see those messages 
indicates to me that DOCboot is doing Something Bad when it loads your 

> My cmdline is:
>   root=/dev/ram0 rootfstype=ext2 ro console=tty0
> I was wondering if the arguments for the cmdline were defined somewhere and
> if there any limitations? For example, does root have to be an mtd device?

No, there should be no such limitations.  I don't think this is user 
error :)

> It sais in the README that there is no serial port support yet the default
> cmdline contains console=ttyS0,115200 - I am a bit confused by this.

What I meant by that is that you can't see the messages printed by 
DOCBoot itself on a serial port, only on your monitor.  Also, there is 
no ability to control DOCBoot from a serial port (using a keyboard, you 
can skip DOCBoot installation).

The information in your cmdline affects the use of the serial port by 
the Linux kernel, not by DOCBoot.

>  I am trying to run the root filesystem from RAM.
> I get the same kernel and initrd file to boot on the same machine from a
> hard diskc using lilo. The lilo stanza for doing this is:
> image = /boot/bzImage
>   root = /dev/ram0
>   label = ramOS
>   initrd = /boot/tiny.image.ext2.gz
>   read-only
> I may be misinterpreting the meaning of the cmdline parameters, but any
> suggestions would be very welcome.

The fact that this works for you in LILO strongly indicates a bug in my 
initrd loading code, which is very simplistic.


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